Ernest gustav hoffmann



(No Model.)

E. G. HOFPMANN. FURNITURB cAsTBR.

Patented Oct. 13,1891.

UNITED STATESv PATENT OFFICE;

ERNEST GUSTAV HOFFMANN, OF N EW SOUTHGATE, ENGLAND.

-FURNITURE-CASTER.

SPECIFICATION forming part of Letters Patent No. 461,181, dated October 13, 1891.

Application filed May 19, 1891. Serial No. 393,270. (NO model.)

To all w'lwm it may conccrn:

Be it known that I, ERNEsT GUs'rAV HoFF- MANN, a subjectof the German Emperor, residing at New Southgate, in the county of Middlesex, England, have invented certain new and useful Improvements in Furniture- Casters, of which the following' is a specification.

My invention relates to improvements in furniture-casters and to the manufacture of same.

The caster is soxnewhat similar to an ordinary one in that it has a portion or basev which is affixed to the article of furniture and a portion pivoted thereto carrying' a roller. Between these two portions I place balls or the like for the purpose of reducing` the friction between the parts, and for this I form channels in one or both of the parts for the balls to Work in. The spindle of the roller is carried in a slot in the forked portion .(which is straight) instead of in a fiXed bearlng, so that it can roll from its center in either direction in order to obtain the rake necessary for readily producing the swivel action. The slot in the forked portion or **horn is curved or angular, so that the roller will be brought to the center of same by the weight of the article of furniture when at rest. In place of carrying the spindle of the roller in slots it may becarried by pivoted arms or cranks or by similar means which will allow it to be thrown out of its center and returned thereto.

In the manufacture of my improved caster I stamp thev parts from sheet-brass or other suitable metal and subsequently shape them by suitable punches, dies, and the like.

To clearly explain the nature of my invention, I will describe it with reference to the accolnpanying drawings, in which' Figure '1 is a front View in section of my improved caster. Fig. 2 is a side elevation. Fig. 3 is a front view in section of a easter provided with an alternative arrangement for carrying the roller, and Fig. 4: is a side ele- -vation of same.

In Fig. 1 the ycaster has the usual base a, carrying a sorew for attaching it to the article of furniture, said base a having an annular groove or race formed on the under side of same for receiving' the anti-friction balls b. which also bear on the upper surface of the h'orn portion c. This horn po'rtion is pro- Vided on either side with curved slots d, as shown, which carry'the spindle f of the roller, the metal of said slot being stamped out in the process of manufacture and turned u p to form an increased bearing portion or ear e for the spindle. In this way the horn portion. may be of comparatively thin metal, which it could not well be if the spindlef had its bearing` only on the edges of a cut slot. To strengthen same the horn is bent and hollowed, as shown, during` the pressing'. The slot CZ, it will be seen, is curved, so that the spindlef will be brought back by the weight of the article directly under the Vertical pressure exerted upon it, which is not the case with the usual curved horn of the ordinary roller-caster, the -tendency of the weight on which is to'break them off from the Vertical spindle on which they turn. The balls Z) also, as will be seen, form an increased bearingsurface, which is of assistance in'taking some of the pressure from the Vertical spindle connecting the base aI and the horn c. The slot d may be angular or of inVerted-V shape,,instead of curved, though it is not so desirable.

In Figs. 3 and 4 I pivot cranks g g to the arms of the horn at the points h h, said cranks carryingthe spindlefof the roller at their other' ends. This acconiplishes the same result as the curved slot, as the crank will fall back into its Vertical position and bring the spindle of the roller directly beneath the Vertical pressure as soon as the article of furniture has ceased to be inoved. In these figures a stamped or drawn cup portion is shown lnstead of the base a and screw, said cup portion having` the groove or race for the balls.

I would have it understood that I do not elaim the use of balls placed between the base and the horn of roller-oasters. Neilher do I elaiin, broadly, the stamping of the parts nor the slotting of the bearing' of the rollerspindle, all of which I am aware have been sug'gested; but

VVhat I claim is- 1. In combination with the base of a caster and the horn or forked portion pivoted thereto, having eentral'bearings, the roller loosely held in said 'bearing's to have lateral movement, butadapted to automatically return to Ico' slots being formed by punohing out the material of the arms and bending thesame upward to form increased bearing for the rollerspindle, substantially as deseribed.

In testimony whereof I have hereunto set my hand in the presence of the two Subscribing witnesses.

E-RNET GUSTAV HOFFMAN N.

lVitnesses:

ALLEN JONES, JosEPH LAKE'. 

